Table

ABSTRACT

Each of a plurality of leg units (U1 to U4) for supporting a top plate (2) have a support column (5) and a foot section (6). The plurality of leg units (U1 to U4) are divided into a first leg unit group (G1) along one long side edge “a” of the top plate (2) and a second leg unit group (G2) along the other long side edge “a”. The first operation units (301) corresponding to the first leg unit group (G1) and the second operation units (302) corresponding to the second leg unit group (G2) are operated individually, to change the lengths of the support columns (5) belonging to the leg unit set (G1) and the second leg unit set (G2) to the different lengths, so that the top plate (2) is tilted.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority from Japan Patent Application No. 2020-92787, filed May 27, 2020, the entire contents of which are herein incorporated by reference.

FIELD OF TECHNOLOGY

This invention concerns a table, which includes a top plate, several support columns which support the top plate and can change its height by operation, and foot sections, each of which is attached to the lower end of the support columns, and can support said support columns at ground level.

BACKGROUND TECHNOLOGY

Conventionally, the structure of such devices as office tables, furniture, setting tables, and working platforms (hereinafter defined as “tables” in this specification as a general term) included a top plate for setting items on its top surface or performing various operations, and one or more support columns to support the top plate. A solution with a height adjustment device for changing the height of the top plate is proposed.

A chair for one person, or a lifting platform for small item display has a narrow top plate area, and only one s support column is usually used to support the seat of the chair and top plate of the table, and an air spring (also known as a “cylinder piston”) is equipped on the support columns. In such devices, a lifting device is proposed for changing and adjusting the height of the seat and top plate by manipulating the length of the support columns. In this lifting device, the support columns is a cylindrical outer column and an inner column that can be loosely inserted inside it. Each end of the air spring is fixed to the inner and outer columns respectively, and the inner and outer columns are guided in the telescopic direction by the nesting of the protrusions and grooves. Both the inner and outer columns are relatively non-rotatable, and the top plate is prevented from rotating with respect the column. The expansion and contraction of the air spring makes it possible to adjust the height of the top plate.

On the other hand, in the case of a table with a corresponding top plate area, a plurality of s support columns with at least two or more air springs should be mounted on the left or right side of the top plate in general (cf. Patent Document 1). In this height adjustment device of the top plate, the lower end of the air spring is supported in a rotatable way, and a special structure with a linkage, rollers, etc. is provided between the upper end of the air spring and the table. Regarding the adjustment of the upper thrust by changing the position of the upper end of the column, the action of the above structure is carried out by means of a shaft part and is linked to the structure on the side of the other column. The adjustment of the top plate height is done by operating with a pedal the air spring set on at least either the left or right of the table, but how to adjust the two air springs when the air springs are set on each column is not disclosed in Patent Document 1.

As an example of a height adjustment device of a top plate supported by two support columns, there is proposed a structure that can change and adjust the length of the two support columns simultaneously with one operation (Patent Document 2). This height adjustment device of the top plate is vertically set on the lifting support columns on both sides of the top plate of the table, and it is set so that it can move upward and downward but cannot move backward and forward. The two lifting support columns are linked by chains engaged around multiple pullies pivotally set on the immovable members of the table, and the rocking plate is pivotally set on the immovable members of the table, thereby the rocking plate and the chains are connected. Further, a screw shaft which has an axis extending in the up-down direction is set pivotally on the rocking plate but does not move up and down on the rocking plate. At the same time, a movable air spring is provided at one end of the immovable member of the table, and the other end of the spring is pivotally mounted on an adjustment fitting threaded to the screw shaft. Thus, in the table supporting the top plate with multiple support columns, in order to move the top plate up and down synchronously and smoothly with all support columns, it is necessary to synchronize the start and end timings and the operation amount of the height adjustment operation. In the height adjustment mechanism of the top plate disclosed in Patent Document 2, it requires a linkage mechanism with a complex structure for the adjustment operation, which takes time to manufacture, assemble and adjust, and also is the reason for the increased cost.

In addition, in the combination of a chair and a table, there is proposed a table in which that changes the front and rear position based on the tilt state of the back of the chair (Patent Document 3). In this table, two metal round tubes are bent into a top view U-shape and an inverted U-shape respectively, and the two metal round tubes have two struts connected by a plurality of connecting members, and the two struts are rotatably supported on the ground by their respective connecting units. The connecting units are mounted on the struts so that the two struts are rotatable between the forward tilting position and the backward tilting position, respectively. The top plate is movable in parallel while remaining horizontal, the top plate of the table is allowed to move backward and diagonally downward depending on the tilt of the chair

In addition, there has been proposed a workstation with a monitor and a keyboard, position of them being changeable according to the posture of the computer user sitting in the chair (Patent Document 4). In this workstation, a hold part can move parallel while maintaining a horizontal state, even when support arms, which corresponds to legs of the table, are tilted. The keyboard base is supported to the hold part, and the keyboard base elevation angle is adjustable by changing the tilt angle relative to the hold part. The keyboard base of this workstation is not support directly to support arms. In addition, the adjustment of the keyboard base elevation angle requires a separate structure, the detailed structure of which is not disclosed in Patent Document 4.

This applicant for this patent has already proposed in the established literature (Patent Document 5) a lifting table with top plate height adjustment device which comprises a top plate and two or three support columns whose lengths are variable to support the top plate. Each support column is equipped with an air spring, such as used in chairs and the like, the length of the support column is variable by changing the length of the air springs with an operation pressing a push valve provided on the upper end of the support column. In general, it is conceivable that two air springs are operated simultaneously by operating a single operating lever, but with respect to such structure, it is inevitable that various errors occur inevitably in manufacturing and assembling the components that form the path from the operating lever to the push valve. It is very difficult, for each table specification, to balance between such manufacturing and assembling errors and the rigidity of the operating rod which leads to deformation and distortion during the operation of the operating rod. That is, if the rigidity of the operating rod is too high, the error appears directly as a difference in timing of pushing the valve, and if the rigidity of the operating rod is too low, the amount of operation of the operating rod is absorbed by the deformation and distortion, and the time of pushing the push valve changes, which does not ensure a sufficient amount of pushing pressure for the valve. The result is that two or more air springs sometimes make it difficult to move up and down equal amounts, that is, it is difficult to carry out synchronized action.

In the lifting table equipped with the above height adjustment device, in order to adjust the height of the top plate, it is proposed to improve the operability of adjusting the table height by coordinating the change of the lengths of any air spring of support columns, although the operation performed by the user is just one simple operation. That is, backlash is provided in the operating path from a handle to the push valve of each support column, and in operating that handle, after all the backlashes are absorbed, by making the operation of pushing down all the push valves start, all the support columns obtain a height adjustment action synchronized in timing and amount of action.

In the lifting table where the above height adjustment is performed, there is not disclosed setting the top plate to an arbitrary tilt angle, and there is no intention to do so. Also, in the form of tilting the top plate relative to a plurality of support columns to change the position of the table in the front-back direction, in many cases support columns are formed in parallel rinks and the top plate is moved in parallel. On the other hand, as an extreme example, depending on what is being worked on the table, such as a drafting table, a lectern, a display table/display stand for merchandise or items, in some cases it is preferable that the top plate can be tilted rather than horizontal. In order to tilt the top plate relative to the support columns performed as parallel rinks, a mechanism for tilting the top plate and maintaining its tilted state is required between the top plate and the top plate support portion set on the upper part of the support columns, and the structure of the upper part of the support column and the top plate support portion has to be more complicated.

PREVIOUS TECHNICAL LITERATURE Patent Literature

Patent literature 1: Texu Bulletin No.11-127964

Patent literature 2: Texu Bulletin No. 10-262741

Patent literature 3: Texu Bulletin No. 4364981

Patent literature 4: Texu Bulletin No. 3642391

Patent literature 1: Texu Bulletin No. 2017-029453

SUMMARY OF INVENTION Subject to be solved with Invention

Therefore, in the table, which includes a top plate, several support columns which support the top plate and can change its height by operation, and foot sections, each of which is attached to the lower end of the support columns, and can support said support columns at ground level, the subject to be solved is how to selectively and easily adjust the height and inclination of the top plate.

The purpose of the present invention is to provide a table capable of adjusting the height of the top plate, by using a mechanism for changing the length of the support columns, even by the user, who can simply configure the structure. The present invention achieves its purpose by providing a lifting table capable of selectively or easily adjusting the height and inclination of the top plate.

Method for Solving the Task

The table of the present invention is provided with a top plate, a plurality of leg units and a plurality of operation units, said each leg unit has a support column and a foot section, said support column has upper and lower ends, the length of the direction connecting the upper and lower ends being changeable, and the upper end being connected to the top plate, and said foot section is connected to said lower end of said support column and is adapted for seating on the floor, said lengths of said support columns of said plurality of leg units are changeable by operating one or more said operation units, wherein said each leg unit belongs to either a first leg unit group which includes one or more leg units and arranged on one side of the top plate or a second leg unit group which includes one or more leg unit and arranged on the other side of the top plate, said each operation unit comprises a first operating section for changing the lengths of the support columns of the leg units belonging to the first leg unit group, and a second operating section for changing the lengths of the support columns of the leg units belonging to the second leg unit group, the second operating section being operable independently of the first operating section.

The table has, as a basic structure, a top plate, a plurality of leg units each having a support column and foot section, and a plurality of operation units, the load of the top plate (including the weight carried on the top plate) being supported on the floor by the leg units. The support column and foot section constitute a leg unit, and said each leg unit belongs to either a first leg unit group which includes one or more leg units and arranged on one side of the top plate or a second leg unit group which includes one or more leg unit and arranged on the other side of the top plate. That is, any support column belongs to either of the first leg unit group or the second leg unit group only, and here, each support column does not belong to the first leg unit group and the second leg unit group at the same time. No leg unit belongs to either leg unit group. The length of the support column of the leg unit belonging to the first leg unit group is changed by operating the first operating section, and the length of the support column of the leg unit belonging to the second leg unit group can be changed by the operation of the second operating section. The length of the support column of the leg unit belonging to the first leg unit group and the length of the support column of the leg units belonging to the second leg unit group can be changed independently by operating the first operation unit and the second operation unit individually. In case the lengths of the support columns belonging to first leg unit group and the lengths of the support columns belonging to the second leg unit group are changed to different lengths, the top plate is tilted relatively on one side to the other side, or can be tilted while changing the height of the top plate. The height of the top plate can be changed when the lengths of all legs are changed to the same length. In addition, because the operation unit is divided into two operating sections of the first operating section and the second operating section, in the case of narrower size of the top plate, even one person user uses both hands to operate each operating section thereby allowing the height and tilt of the top plate to be adjusted, and in the case of a wider width of the top plate, two people can operate operation units by sharing the on each side of table, and the height and tilt of the top plate can be adjusted.

In this table, the foot section of said each leg unit comprises a foot body portion which is mounted on said support column and extends in a direction between said one side of the top plate and the other side, and plurality of foot portions which are spaced in the direction of their extension and are adapted for seating on the floor.

When the top plate is in a tilted state with one side relative to the other side, the position of the table's center of gravity is moved causing load imbalance. On the table acts a moment which tends to make the the table tip in the tilt direction connecting one side and the other said of the top plate. Each leg section is provided by spacing with the foot portions that are adapted to land on the floor in the tilt direction. The counteracting moment is obtained with a reaction force from the floor to the foot portions, the resistance to table tipping can be improved by this counteracting moment.

In this table, the foot body portion of said leg unit is fixedly mounted on said support column, the foot portions are mounted on said foot body portion in a manner that the length of each foot portion protruding relative to the foot body portion in the direction to the floor can be changed, said protruding lengths of said foot portions relative to the foot body section can be changed corresponding to the tilt angle of the top plate.

The foot body portion is fixedly mounted on the support column, the foot body portion also tilts together with the support column when the top plate and support column tilt. Due to the special mounting structure in which the foot portions are mounted on said foot body portion in a manner that the length of each foot portion protruding relative to the foot body portion in the direction to the floor can be changed, even if the foot body portion tilts according to the tilt of the top plate, each foot portion can be on the floor in its own way and can transfer the load of the table to the floor by adjusting the protruding height in the direction. In this case, each foot portion includes a joint structure such as a ball joint, and the foot body portion is supported so that each foot portion is preferentially seated on the ground in its own way, even if it is tilted with the support column.

In this table, the foot body portion of said leg unit is mounted on said lower end of the said support column in a manner that the mounting angle can be changed,

the mounting angle of the foot body portion relative to said support column can be changed corresponding to the tilt angle of the top plate.

Since it is possible to change the mounting angle of the foot body portion relative to the lower end of the support column, even if the support column tilts corresponding to tilting of the top plate, the mounting angle of the foot body portion relative to the support column can be changed according to the tilt of the support column, so that any foot portions can land on the floor in its own way, and the table can transmit the load to the floor. Since the foot body portion and the foot portions can be an integrated structure, the foot part can be constructed as a simple structure.

In this table, both the first and second leg unit groups have more than two leg units, the support columns of the leg units belonging to the first leg unit group are in a common first support column configuration plane, the support columns of the leg units belonging to the second leg unit group are in a common second support column configuration plane, and said first configuration surface and second configuration surface are parallel to each other.

When operating the first operation section to change the length of the support columns of the leg units belonging to the first leg unit group, all support columns of the leg unit belonging to the first leg unit group and arranged in a common first support column configuration plane synchronize and be adjusted to the same length. When operating the second operation unit, all support columns of the leg unit belonging to the second leg unit group and arranged in a common second support column configuration plane synchronize and be adjusted to the same length. In making the lengths of the support columns of the leg units belonging to the first leg unit group and belonging to the second leg unit group to the same length, only the height of the top plate is changed, and when the two lengths are changed to different lengths, the top plate is tilted according to the difference in length, or it can be tilted while changing the height of the top plate.

In this table, said foot portions mounted on the support columns of the leg unit belonging to the first leg unit group and said foot portions mounted on the support columns of the leg unit belonging to the second leg unit group are connected by the connecting member so that the relative position changes of the both said foot portions resulting from the inclination of said top plate can be absorbed.

The connecting member connects foot portions mounted on the support columns of the leg unit belonging to the first leg unit group and said foot portions mounted on the support columns of the leg unit belonging to the second leg unit group, in the state of absorbing the changes of relative spacing and rotation of the two foot sections approaching and separating from each other according to the tilt of the top plate. Further displacement or deformation of the two foot sections that increases the relative spacing or rotation of the two foot sections in connected state can be prevented, and displacement or deformation of the two foot sections in connected state that causes the relative lateral movement or twisting can be suppressed. The leg and foot structure can improve the rigidity of the structure and contribute to stability.

In this table, said leg units includes four leg units, each arranged at point corresponding to the four vertices of the parallelogram, said one side and said other side of the top plate are the two opposite sets of sides of said parallelogram, with respect to each of the two sets of sides of the top plate, said foot units are defined as belonging to either a first leg unit group or a second leg unit group, and two operating sections are defined as belonging to either a first operating section or a second operating section.

Regarding this table, there exists two pairs of opposite sides in the table, each set consisting of one side and the other side of the table, because with respect to each of two pairs of opposite sides in a parallelogram, there are one side and the other side. With respect to the four leg units, two leg unit group are determined in each pairs of sides of the table. With respect to the operation unit, a first operation section and a second operation section for operating the two leg unit groups are provided in each pairs of sides of the table. That is, since there are two sets of operating sections with respect to the first and second operating sections, the set of operation units to be operated in the case of tilting the top plate is selected according to the tilting direction selected between the two tilting directions.

In this table, said each leg unit includes a top plate support structure that is mounted on the top plate and the upper end of the support column, for connecting the upper end of the strut to the top plate, in each of said leg units, one of the operating sections belonging to said first operating section and one of the operating sections belonging to second operating section extends into said top plate support structure, and the length of the support column can be changed by operating either of said two operating sections.

In this table, in order to support the top plate, corresponding to the four vertices of the parallelogram (four corners), the top plate receiving structure is mounted in the upper end portion of each support column, one of one set of operation units and another set of operation units is extended along the two sides across each corner and into the top plate receiving structure. For each support column corresponding to the four corners, the length of support column is set to be changeable by operation from any of the operating sections on either side. Thus, the top plate is tilted in one of the two groups on one side and the other side, and since it can be operated on either group, the top plate can be tilted in one of the two tilt directions.

In this table, the foot sections are rotatably mounted on said support columns according to the selected tilt direction so that the direction in which said foot body portion extends follows said tilt direction.

The foot section is mounted in a rotating form relative to the support column with a direction of its extension in line with the direction of tilt according to the selected direction of tilt. By making the foot section rotate relative to the column, the foot section can readjust the tilt to the selected group even in the case of tilting on the other side because it can make the direction of extension coincide with the direction of tilting with the top plate. Therefore, this structure can easily counteract the tipping moment of the table due to tilting.

In this table, the height of the top plate can be changed by changing the support column lengths of the leg units belonging to the first and second leg unit groups to the same length.

With respect to wide table with four support columns, one person cannot operate the table with two operating sections of horizontal length at the same time. Even in the case of two people operating, the invention can change the height by operating equal amounts separately.

EFFECT OF INVENTION

The table of this invention can have the following unique effects.

This table has, as a basic structure, a top plate, a plurality of leg units each having support column and foot, and a plurality of operating portions, each leg unit belonging to either a first leg unit group provided on one side of the top plate or a second leg unit group provided on the other side of the top plate; the support columns of the leg units belonging to the first leg unit group are variable in length by operating the operating portion, and the supports of the leg units belonging to the second leg unit group. The length of the support column of the leg unit belonging to the first leg unit group and the length of the support column of the leg unit belonging to the second leg unit group are changed by the operation of the first operation section or the second operating individually. When the lengths of the support columns are changed to the same length, the height of the table is changed. When the lengths of the support columns are changed to the different lengths, the table is tilted from one side to the other side, or the height and tilting of the table are changed. Since the operation unit is divided into two operation units of the first operation section and the second operation section, the user can make height adjustment and tilt adjustment by operating each operation section alone. Alternatively, two people can operate the respective operation sections. Each of the first operation section and the second operation section is itself a mechanism for changing the length of the leg unit which has been used in a lifting table capable of changing the height of the top plate. The table of this invention is provided, by utilizing and devising this mechanism, in which the structure thereof can be made as simple as possible, and the height and tilting of the top plate can be easily adjusted by operating the first operation section and the second operation section individually.

BRIEF DESCRIPTION OF DRAWINGS

FIGS. 1A-1C are views of the first embodiment of the table according to the present invention.

FIG. 2 is a perspective view showing a part of the table shown in FIGS. 1A-1C when viewed from the inside.

FIGS. 3A-3C are views explanatory views showing the structure of the leg unit of the table shown in FIGS. 1A-1C.

FIGS. 4A-4C are views showing an operation unit of the table shown in FIGS. 1A-1C.

FIGS. 5A-5B are explanatory views showing the inclination of the top plate of the table shown in FIGS. 1A-1C.

FIGS. 6A-6B are perspective views showing the second embodiment of the table according to the present invention.

FIGS. 7A-7B are explanatory views showing the connection structure of a foot section and a support column of the leg unit shown in FIGS. 6A-6B.

FIGS. 8A-8B are perspective view showing the third embodiment of the table according to the present invention.

FIG. 9 is a perspective view showing the fourth embodiment of the table according to the present invention.

FIG. 10 is a perspective view showing the fifth embodiment of the table according to the present invention.

FIG. 11 is a perspective view showing the operation sections and top plat support structure in the embodiment shown in FIG. 10.

FIGS. 12A-12D are explanatory views showing the rotational configuration of the foot section of the leg unit of the table according to the present invention.

FIGS. 13A-13B are schematic diagrams showing the sixth embodiment of the table according to the present invention.

FIGS. 14A-14B are schematic diagrams showing other embodiments different in top plate shapes of the table according to the present invention.

DETAILED DESCRIPTION

Referring now to the embodiments of the invention shown in the attached drawings, FIGS. 1A-5B are drawings representing an embodiment of the table. FIGS. 1A-1C show a perspective view and a side view of the first embodiment of the table according to the present invention. FIG. 2 shows a perspective view representing a portion of the table when viewed from the inside. FIGS. 3A-3C show the leg unit of this table, i.e., a leg structure including a support column and a foot section, and a top plate receiving structure for connecting the top plate and the support column. FIGS. 5A-5B are explanatory views showing the inclination of the top plate of the table.

FIGS. 1A-1C represent an implementation example of the table according to the present invention. FIG. 1A is a perspective view showing the table in which the top plate is in a high position and in a horizontal state, FIG. 1B is a side view thereof, and FIG. 1C is a side view showing the table in which the top plate is in a low position and in a horizontal state. The table 1 includes a top plate 2, a leg structure 3 for supporting the top plate 2 on a surface F and an operation unit for tilting the top plate 2 (see FIG. 2 and FIGS. 4A-4C, etc. for details, as the operation unit 30 will be expressed later). The top plate 2, can be made of various materials such as resin, metal, and glass.

In the case of this embodiment, the top plate 2 is a plate that is rectangular in a plane view and is most commonly used as a top plate of the table for office use or for work. The top plate 2 is supported on the floor surface F by a leg structure 3 consisting of four leg units U1 to U4 in the four corners corresponding to the top plate 2. Each leg unit U1 to U4 has a support column 5 of variable length on the upper end of which is mounted the top plate 2, and a foot section 6 mounted on the lower end of the support column 5. In case the upper end of the support column 5 is mounted on the top plate 2 by means of a top plate receiving structure 4 mounted slightly inboard of each corner of the top plate 2, Each leg unit U1 to U4 may include the top plate support structure 4. The load of the top plate 2 and objects placed on the top plate 2 is transferred from the top plate receiving structure 4 to the support column 5, and the load applied to the support column 5 is supported on the ground F via the foot section 6. In this embodiment, each support column 5, as shown in FIG. 1B and FIG. 1C, has a top plate supporting structure 4 mounted on its upper end 5 a, and is mounted at its lower end 5 b in an upright setting relative to the foot section 6. In each leg unit U1 to U4 of the leg structure 3, the top plate support structure 4, the support column 5 and the foot section 6 have substantially the same structure. Thus, each leg unit U1 to U4 at the four corners have the same structure except for the different orientation of the arrangement around the longitudinal axis of the support column 5.

In this embodiment, four leg units U1 to U4 are arranged along the long side edges “a”, “a”, and are classified into two leg unit groups, i.e., the first leg unit group G1 and the second leg unit group G2. Each leg unit U1 to U4 belongs to either of the leg unit groups G1 or G2. The first leg unit group G1 arranged along one long side edge “a” of the top plate 2 (the front side in FIG. 1A, the left side in FIG. 1B and FIG. 1C) consists of two leg units U1, U2, and the second leg unit group G2 consists of two leg units U3, U4 arranged along the other long side edge of the top plate 2. There is no leg unit which belongs to both leg unit groups G1, G2, and there are no leg units that do not belong to either leg unit group G1 and G2. In this embodiment, the first leg unit group G1 and the second leg unit group G2 are arranged substantially symmetrically with respect to the vertical planes including the lateral center line L-L which connects the respective intermediate positions of the short side edges “b”, “b”. It should be noted that the top plate 2 is in a horizontal state when the lengths of the leg units U1 to U4 (i.e., the length of each support column 5) are equal.

The longitudinal centerline (in line with the centerline of the long axis direction of the support column 5) of each leg unit U1 to U4, mounted on the top plate 2 through the top plate receiving structure 4, is perpendicular to a plane defined with respect to the top surface of the top plate 2. The top plate 2 and each leg unit U1 to U4 are always in an orthogonal state. As shown in FIG. 1B and FIG. 1C, the support column 5, 5 belonging to the first leg unit group G1 are arranged in a common first support column configuration plane P1 parallel to one long side edge “a”, and the support column 5, 5 belonging to the second leg unit group G2, 5 are arranged in a common second support column configuration plane P2 parallel to the other long side edge “a”. The first support column configuration plane P1 and the second support column configuration plane P2 are parallel to each other. The support column 5, 5 of the leg units U1, U2 belonging to the first leg unit group G1 are adjusted synchronously to the same first length, and the support column 5, 5 of the leg units U3, U4 belonging to the second leg unit group G2 are adjusted synchronously to the same second length. The top plate 2 is adjusted to a tilted state, when the first length and the second length are different lengths. When an attempt is made to tilt the table 1, the operation of the operation unit 30, as shown by the arrow T in FIG. 1A, causes the top plate 2 to tilt in the tilting direction. That is, in the case of this embodiment, the top plate 2 is tilted in such a way that the long side edges “a”, “ a” is maintained in a horizontal state while the shorter side edges “b”, “b” is tilted in a vertical direction.

In the table 1, the top plate 2 is placed, at its four corners, on the leg units U1 to U4, and supported on the ground F by the foot section 6 set on the lower end of each support column 5. Each foot section 6 has a foot body portion 7 in the shape of one square tubular and a plurality (in this example, two) of footing portions 8, 8, the foot body portion 7 being fixedly mounted on the lower end portion 5 b of the support column 5, and footing portions 8, 8 being mounted on the foot body portion 7 in the longitudinal direction thereof and spaced apart relative to each other at the positions on both sides of the support column 5 and adapted to seat on the ground F. The foot body portion 7 extends in the direction parallel to the short side edges “b”, “b” of the top plate 2 corresponding to that inclination direction, when assuming an inclination of the top plate 2.

In each foot section 6, one foot portion 8 passes through the foot body portion 7 and extends upward, and the mounting position of the foot portion 8 in the height direction relative to the foot body portion 7 is changeable by means of the foot axis 9 for when trying to tilt the top plate 2. One foot portion 8 has a variable height of protrusion to the ground F side relative to the leg body portion 7 according to the angle at which the top plate 2 is tilted, but the other leg portion 8 is fixed without penetrating the foot body portion 7 in a way that is buried in the foot body portion 7. In the case of the tilted state of the top plate 2 raised on the side of the second leg unit group G2, a long foot shaft 9, 9 that penetrates the foot body part 7 is used in the foot portions 8, 8.

The foot sections 6, 6 (first foot section group 6G1) mounted on the two support columns 5, 5 of the leg units U1, U2 belonging to the first leg unit group G1 are connected to each other by an elongated foot connector 10. The foot connector 10 has a function of increasing unity(rigidity) of the first leg unit group consisting of the leg units U1, U2. For the foot sections 6, 6 (second foot section group 6G2) of the leg units U3, U4 belonging to the second leg unit group G2, another leg connector 10 improves the unity(rigidity).

The foot connectors 10,10 are bent to each other and close to the central side in order not to obstruct the feet of the user using the table 1. The foot connectors 10,10 may be made in the straight shape as shown by imaginary lines, if they do not obstruct the feet of the user using the table 1. The foot connectors 10 a,10 a can be made of a bar or barrel material having a suitable cross-sectional shape, and in addition. Each support column 5 may be mounted on the connector 10 for connecting the foot sections 6, 6, instead of being mounted to the foot body portion 7 itself.

As described later, the support column 5 have a nested outer cylinder 11 and an inner cylinder 12, and in the event that the outer cylinder 11 and the inner cylinder 12 do not adequately ensure the length of the support column 5, a complementary connecting cylinder 5 c can be used in the manner of replenishment to the outer cylinder 11 (refer to FIGS. 7A-7C for details). Since the length of support column 5 is variable, each support column 5 has a locking structure 17 for maintaining the length of the support column 5. The locking structure 17 holds the inner cylinder 12 at the upper end of the outer cylinder 11, and well-known grasping tools as fastening structure can be used. Although not illustrated in detail, the several fastening structures can be used, such as a fastening structure provided inside the outer cylinder 11 presses the cam member against the outer side of the inner cylinder 12 and grips it, and a fastening the structure on the outer cylinder 11 clamps the inner circumference of the installed locking structure 17 relative to the circumference of the inner cylinder 12 by friction. Further, like the locking structure 17 a shown in FIG. 3A and FIG. 3B, a small screw is screwed into the cap body mounted on the upper end of the outer cylinder 11, and a structure that presses the front end thereof against the outer side of the inner cylinder 12 can also be used. The locking structure 17 or 17 a prevents the support column 5 from accidentally shortening in length caused by the inner cylinder 12 descending in the outer cylinder 11 even when a large load is applied to the top plate 2.

FIG. 2 is a perspective view showing a part of the table shown in FIGS. 1A-1C when viewed from the inside. In FIG. 2, the same reference numbers or codes as those used in FIGS. 1A-1C are used to the same or corresponding elements and parts as those shown in FIGS. 1A-1C. A rod-like first operation unit 301 is arranged along one side edge “a” of the top table 2 for the leg units U1, U2 belonging to the first leg unit group G1 provided corresponding to said one side edge “a”, and a rod-like second operation unit 302 similar to the first operation unit 301 is arranged along the other side edge “a” of the top table 2 for the leg units U3, U4 belonging to the second leg unit group G2 provided corresponding to said the other side edge “a” (the operation unit is indicated as unit 30 when the operation section 301 and 302 are referred to in general). With respect to the two leg unit groups G1 and G2, the first operation unit 301 and the second operation unit 302 are operated individually, so that the support columns 5, 5 of the leg units U1, U2 belonging to the first leg unit group G1 and the support columns 5, 5 of the leg units U3, U4 belonging to the second leg unit group G2 can be operated separately. According to the operation section 30, the air springs, more specifically the push valves set in the air springs, are operated synchronously as adjustment mechanisms which are provided for changing the lengths of the support columns 5, 5 of the two leg units belonging to each leg unit group G1, G2. Details about the section 30 will be described later with reference to FIGS. 3A-3C and FIGS. 4A-4C.

FIGS. 3A-3C illustrate the support column of the table, the top plate receiving structure associated with it, and the foot section in detail. In FIGS. 3A-3C, the same reference numbers or codes as those used in FIGS. 1A-1C are used to the same or corresponding elements and parts as those shown in FIGS. 1A-1C. FIG. 3A shows the leg unit, i.e., the foot structure including the support column and the foot section, and the top plate receiving structure. FIG. 3B is an enlarged view indicating the details of the top plate support structure, which is intervened between the top plate and the support column in order to connect them. FIG. 3C is an enlarged cross-sectional view indicating the details of the foot section. As shown in FIG. 3A and FIG. 3B, each support column 5 of the leg unit (the leg unit U2) is provided with the inner and outer cylinders (outer cylinder 11 as an air spring cover and inner cylinder 12) which are inserted and fitted to each other into a nested shape as a support column length adjustment mechanism, an air spring 13 is built in the inner cylinder 12. The outer cylinder 11 and the inner cylinder 12 can slide relatively in the guided longitudinal direction (the standing direction of the support column) by the sliding structure, for example, formed in the upper end of the outer cylinder 11 and the convex shape of the inner cylinder 12. The lower end of the inner cylinder 12, although not shown, can slide relative to the inner circumference of the outer cylinder 11 by an appropriate slider. The locking structure 17 a of the outer cylinder 11 and the inner cylinder 12 is illustrated. The embodiment shown in FIGS. 3A-3C does not use a replenishment cylinder 5 c for extending the length of the support column 5.

The outer cylinder 11 (the connecting cylinder 5 c in the case where the connecting cylinder 5 c is attached below the outer cylinder 11) is mounted with the lower end 14 (equivalent to the lower end 5 b of the support column 5) standing on the foot body portion 7. The top plate receiving structure 4 mounted on the lower surface of the top plate 2 and the upper end 15 of the inner cylinder 12 (equivalent to the upper end 5 a of the support column 5) are made of iron or resin such as polypropylene reinforced by fiberglass, and each of them may be manufactured separately, and a plurality of parts or materials can be assembled by fixing, for example, with blind rivets and the like. They can be also manufactured by integral molding. In addition, the structure of each support column 5, as the table of the present applicant, is disclosed in the application that has been filed (Patent literature 5).

Each support column 5 has air spring 13 built in, the length of which can be changed by operating the operation unit 30. As for the air spring 13, although not specifically illustrated, a well-known structure can be used, which has a cylinder and piston rod being able to enter and exit by sliding relative to the cylinder, such as used in the field of the chair. Also, as for the air spring 13, the lower base end portion of the cylinder is fixed to the lower end portion 14 of the outer cylinder 11, and the upper end of the piston rod is fixed to the upper end 15 of the inner cylinder 12. The load acting on the top plate 2 is transmitted to the ground F from the top plate receiving structure 4 mounted directly on the top plate 2 via the support column 5 through the leg structure 3. That is, this load is transmitted, in each support column 5, from inner cylinder 12 via the air spring 13 and the outer cylinder 11, to the foot structure 3, and supported on the ground F.

Referring to FIG. 3A and FIG. 3B, the top plate receiving structure 4 is overall a substantially U-shaped groove structure or a disc-shaped structure having a square shape, having a disc-shaped side wall portion 22 and a bottom wall portion 23 forming inside a central concave portion 21 in the interior. A flange portion 26 having a flat surface is continuously formed to the upper end of the side wall portion 22. In a state that the flat surface of the flange portion 26 is in contact with the lower surface of the top plate 2, the flange portion 26 is attached to the top plate 2 by an appropriate fastener 24 (marked for a portion only), such as a blind rivet, as a result the top plate receiving structure 4 is mounted on the top plate 2. The top plate receiving structure 4 may be a structure in which the side wall portion 22 and the bottom wall portion 23 are molded in one piece and may be manufactured separately and secured with something obtained by a fastening tool such as a blind rivet. The top plate receiving structure 4 may have the side wall portion secured to the top plate 2 at the appropriate location of 22, and may also be secured from the lower side of the top plate 2. That is, the top plate receiving structure 4 is applied to the lower side of the top plate 2, sticking blind rivets through the side wall portion 22 into the top plate 2 from the lower side thereof, so that the top plate receiving structure 4 is attached to the top plate 2 without rivets sticking out on the upper surface side of the top plate 2. Regarding the top plate receiving structure 4, although it is an alternative embodiment, a perspective view is also shown in FIG. 11.

In order to make it possible to operate the air spring 13, the upper end of the piston rod protrudes through the upper end portion 15 of the inner cylinder 12 toward the internal space determined by the central concave portion 21 of the top plate supporting structure 4, and the push valve 16 of the air spring 13 is exposed in the internal space. To operate the push valve 16 exposed into the interior space, the operation tip portion of the operation unit 30 extends into the interior of the top plate receiving structure 4. The push valve 16 is pushed in by operating the operation portion 30, whereby the movement of the gas within the air spring 13 is controlled and the piston rod advances or retracts from the cylinder. By such action of the air spring 13, the inner and outer cylinders 11 and 12 perform a telescopic action, changing the length of the support column 5. Depending on the weight placed on the top plate 2 of the table 1, the gas pressure (5 kg, 8 kg, 10 kg, 20 kg, etc.) inside the air spring 13 is adjusted. The structure of the operating section 30 inside the top plate support structure 4 (connection 34 and the lever pivot part 35, etc.) to operate the air spring 13 will be described later referring to FIGS. 4A-4C (FIG. 11).

FIG. 3C is an enlarged view showing the foot section 6 of the foot structure 3. In FIG. 3C, one foot section 6 to be attached to one support column 5 is shown, other foot sections also have the same structure. In the illustrated example shown in FIGS. 3A-3C, foot portions mounted on the foot body portion 7 of the foot section 6 are the foot portion 8 a having a foot shaft 9 b and the foot portion 8 b having a short foot shaft 9 b. The foot shaft 9 a of the foot portion 8 a is longer than the foot shaft 9 b of the foot portion 8 b, as will be described later. In the hypothetical tilted state of the top plate 2, where the first leg unit group G1 is raised, the foot body portion 7 of any foot section 6 is raised on the long foot shaft 9 a than the short foot shaft 9 b. At the lower end of the foot shafts 9 a, 9 b, the seating body 8 c on the ground F is mounted. The seating body 8 c is formed as a roughly conical body and contacts the floor surface F on the wide seating surface.

When the top plate 2 is set to a tilted state, the center of gravity as a whole on the table 1 moves in the tilted direction. Load imbalance causes a tilting moment that tends to fall the table 1 in the tilted direction as a whole. The support column 5 is secured to the foot body portion 7 in the position biased to the side lifted by tilting (foot portion 8 b side) with respect to the longitudinal center position of the foot body portion 7. By fixing the support column 5 to the foot body part 7 in the offset position, it is possible to make the distance d2 from the attachment position of the support column 5 to the foot portion 8 b extending to the downwardly inclined side longer than the distance d1 from the attachment position of the support column 5 to the foot part 8 a extending to the upwardly inclined side, and the foot part 8 b can be mounted at a position away from the support column 5.

Such a structure makes it easy to obtain the large countering moment acting on the table 1 when the lifting platform 1 is tilted, based on the reaction force acting from the floor surface F on the foot portion 8 b on the downwardly inclined side. That is, the footing portions 8 a, 8 b of each foot section 6 are spaced apart in line with the tilting direction and in line with longitudinal direction thereof, and the lower end portion 5 b of the support column 5 is intervened between the footing portions 8 a, 8 b, the distance of the support column 5 from the lower end portion 5 b to the foot portion 8 b extending down the tilting side is set to a larger configuration. As a result, even if a tipping moment is generated on the table 1, it is possible to obtain the large moment countering to the tipping moment, based on the reaction force acting on the foot portion 8 a, 8 b from the floor surface F, and resistance to a fall of the table 1 can be improved.

For the longer foot shaft 9 a, as shown in the example of FIG. 3C, it is constituted on the screw shaft 40. By means of two nuts 41, 42 screwed to the screw shaft 40 from the upper and lower sides of the foot body portion 7, the foot shaft 9 a is fixed to the foot body portion 7 at any height position in the direction of its axis, and slackness can be prevented by washers 43, 44 interposed between the nuts 41, 42 and the foot body portion 7. For the shorter foot shaft 9 b, a threaded shaft 45 likewise as a screw shaft 40, is fixed to the foot body portion 7 by screwing the screw shaft 45 into the threaded hole 46 formed in the foot body portion 7. Joint structures such as a ball and socket joints 47 are provided at the connection portions between the foot shafts 9 a, 9 b and the seating body 8 c by using a structure, so that the seating body 8 c is square to the ground F even if the foot shaft 9 b or 9 b is tilted, i.e. it can be seated in the original manner. Alternatively, for shorter foot shaft 9 b, the foot portion 8 b is screwed into one of a plurality of screw-in positions (e.g., a plurality of threaded holes 46 b) relative to the foot body portion 7, or the foot portion 8 b is made slidable relative to the foot body portion 7. The installation position can also be selected according to the degree of tilt utilized.

With respect to the lengths of the support columns 5, 5 belong to the first and second leg units U1, U2 of the first leg unit group G1, and the lengths of the support columns 5, 5 belong to the third and fourth leg units U3, U4 of the second leg unit group G2, the lengths of the former and the lengths of the latter can be changed respectively(independently), and within each leg unit group G1, G2, the lengths of the former and the lengths of the latter can be separately. In order to coordinate such length changes between the former and the latter, an operation unit 301 is provided for the leg unit group G1 and an operation unit 302 is provided for the leg unit group G2 (refer to FIG. 2). When the user performs the operations of the operation unit 301 and 302 individually, the support columns 5, 5 of the first and second leg units U1, U2 belonging to the first leg unit group G1 can be coordinated to change their lengths to the same length; the support columns 5, 5 of the third and fourth leg units U3, U4 belonging to the second leg unit group G2 can also be coordinated to the same length. The operation units 301 and 302 can be operated independently of each other without mutual influence, so that independent operation of the operation units enables the lengths of the first leg unit group G1 and the second leg unit group G2 to be different lengths according to the amounts of operations and the top plate 2 to be tilted relatively to one side so that the other side is tilted relatively, or the height of the top plate 2 can be changed and further tilted. Even if the user is a person, the tilt of the top plate 2 can be adjusted by operating the operating portions 301 and 302 individually. When the user operates the operation unit 301 and 302 with the same amount, the height of the top plate 2 can be changed.

FIGS. 4A-4C illustrate a detail of an operation unit for tilting the table. FIG. 4A is a perspective view showing the whole of this operation unit and the top plate receiving structure with the inner side as the surface side, and FIG. 4B is a perspective view showing this operation unit and the top plate receiving structure as a part of the operation unit shown in FIG. 4A and the top plate receiving structure on one side, as viewed from the surface side. FIG. 4C is a partial cross-sectional view showing the details of the L-shaped connecting member. Regarding the operation units 301, 302, for simplicity, only one operating section (reference numeral 30 is used as a symbol for the general term for the operating section containing each constituent element) is described. The operating section 30 includes the handle portion 31 extending straitly along the long side edge “a” (cf. FIG. 2) and operation rod section 32, 32 extending individually from the handle portion 31 into the top plate support structures 4, 4 provided corresponding to all the support columns 5 (in this example, two support columns) belonging to the same group of leg units and for operating an air spring 13 (cf. FIG. 3A). The operating rod section 32, 32 extend in the right and left directions from the handle portion 31 individually, each operating rod section 32 includes the first rod portion 33 a extending straitly, the L-shaped connector 34 provided at the front end of the first rod portion 33 a and the second rod portion 33 b extending from the connector 34 longitudinally (thus, perpendicular to the first rod portion 33 a) and straightly into the top plate receiving structure 4. The first rod portion 33 a and the second rod portion 33 b constitute a plurality of rod portions (collectively referred to as the symbol “33”) connected by the connector 34. In order to make it easy for the user to grasp the handle portion 31 by hand, the handle portion 31 is formed in a curved shape toward the front side (indicated by an imaginary line).

As shown in FIG. 4A and FIG. 4B (also FIG. 1B and FIG. 1C), in the operating section 30, the axis of the handle portion 31 and the axis of the operating rod portion 32, 32 which include the first rod portions 33 a, 33 b, connectors 34, 34 and the second rod portions 33 b, 33 b are arranged in the one common plane. By arranging the axes of the operation unit 30 to be in a common plane, errors and gaps in the structure of the operation unit 30 are reduced and the correctness of the action when operating the operating section 30 is increased. Each second rod portion 33 b extends through the long hole 25 formed longitudinally in in the disk-shaped sidewall portion 22 of the top plate receiving structure 4 into the central concave portion 21 of the top plate supporting structure 4, the front tip portion of the second rod portion 33 b is formed as a flat air spring operating portion 36. The second rod portion 33 b is supported in the top plate receiving structure 4 in a manner that the second rod portion 33 b can incline vertically at the lever pivot portion 35 formed in the middle of the length thereof. When a user grasps the handle portion 31 by hand and brings the operating portion 30 close to the direction (direction intersecting the paper and going to the back of the paper in FIG. 4A) of the top plate 2, the second rod portion 33 b of each operating rod portion 32 performs a rotating action by lever action relative to the top plate receiving structure 4 at the lever pivot portion 35 as the pivot point, and the air spring operating portion 36 rests against the push valve 16 of the air spring 13. Both operating rod portions 32, 32 simultaneously push down the push valve 16, 16, to activate both air springs 13,13. Also, with respect to the top plate receiving structure 4, the bottom wall portion 23, the flange portion 26 and the fixing member 24 have been described in FIGS. 3A-3C.

As shown in FIG. 4C, the L-shaped connector 34 has two holes 34 a, 34 a, one hole 34 a formed at one end for insertion of the first rod portion 33 a and the other hole 34 a formed at the other end for insertion of the second rod portion 33 b. Each hole 34 a has an inner diameter insertable with the first rod portion 33 a and the second rod portion 33 b and sufficient clearances Ga, Gb are left between the end faces of the first and second rod portions 33 a, 33 b and the bottoms of holes 34 a, 34 a, respectively. The connector 34 has threaded holes 34 b, 34 b formed from its outer side thereof in an open manner crossed and opened to the holes 34 a, 34 a. Small screws 34 c, 34 c contact the inserted first rod portion 33 a and second rod portion 33 b by screwing into the holes 34 b, 34 b, and the two rod portions 33 a,33 b can be fixed to the connector 34 in their positions and postures. With respect to the connector 34, sufficient rigidity and strength is provided so that it does not substantially deform under normal operating forces, and the threaded holes 34 b, 34 b are made of metal or nylon (reinforced with fiberglass) so that the threaded slots 34 b, 34 b are not prone to rusting and breaking.

In the fabrication of the operation unit 30, machining errors or assembly errors may arise due to machining or assembly incorrectness. For example, the handle portion 31, the first rod portion 33 a, 33 a and the second rod portion 33 b, 33 b are not precisely in one plane, the first rod portion 33 a and 33 a are not integrated in one common line, and furthermore there is even the second rod portion 33 b and 33 b are not parallel to each other. In these cases, it will be extremely difficult to operate the push valve 16,16 of the air spring 13,13 simultaneously and in equal amounts by the handle portion 31 alone. In addition, in the case of making the first rod portion 33 a,33 a and the second rod portion 33 b,33 b as one continuous and integral piece from a long rod material without using the connector 34,34, it is difficult to make the two sets of first and second rod portions 33 a and 33 b to be arranged in one plane. When increasing the rigidity of the rod as one piece, the push valve 16,16 of the air spring 13,13 work at different operation timings, which makes difficult the tuning action of the push valve 16,16. On the contrary, when decreasing its rigidity, large deformation of bending or twisting is easily produced at the bent portion from the first rod portion 33 a to the second rod portion 33 b, and even if the operating amount of the handle portion 31 is increased, the operating amount cannot be transferred to the second rod portion 33 b,33 b, eventually resulting in the inability to fully press the push valve 16,16. In this case, it takes much time to change the height of the top plate 2.

According to the operation unit 30 of this embodiment, by using the connector 34, in the state before fixation, the connector 34 is allowed to rotate around two axis (axis 0 of the first rod portion 33 a and axis δ of the second rod portion 33 b) for the first rod portion 33 a and the second rod portion 33 b. Also, in the state before fixation, the first rod portion 33 a and the second rod portion 33 b can move within the allowed range defined by the gap Ga and a gap Gb in the axis direction X of the first rod portion 33 a and the axis direction Y of the second rod section, respectively. Because such rotation and movement are allowed, the handle portion 31 of the operation unit 30 is operated in the state of loosening the small screws 34 c, 34 c, the insertion amount and rotation angle amount of the first rod portion 33 a, 33 a and the second rod portion 33 b, 33 b relative to the connectors 34, 34 are adjusted so that both of the air spring operating portions 36, 36 formed at the tip end of the second rod portion 33 b, 33 b contact with the push valve 16, 16 of the air spring 13, 13 (only in contact with it, not pushed in). In this contact state, the small screw 34 c, 34 c is screwed into the connectors, even after the operation of the operation unit 30 is released, the first rod portion 33 a, 33 a and the second rod portion 33 b, 33 b are holed in fixed condition to the connector 34, 34, and the operation unit 30 is maintained in an integrated structure as a whole. After absorbing such errors and gaps and maintaining a fixed state, the user operates the operation unit 30, and with the help of the high rigidity of the connectors 34, 34 against bending and twisting deformation, an operation on the handle portion 31 is not absorbed in the middle of the path, and is transferred to the air spring operation section 36, 36 of the second rod portion 33 b, 33 b, which tunes to the operation of the push valve 16, 16 of the air springs 13, 13, that is, the second rod portion 33 b, 33 b are in contact with the push valve 16, 16 at the same time and can be pushed in equal amounts. In this way, even if the handle portion 31, the first rod portion 33 a, 33 a and the second rod sections 33 b,33 b do not have precise alignment and parallelism in the manufacturing process, the operation unit 30 is assembled together with the top plate receiving structure 4, 4 in the state without manufacturing errors caused by both processing and assembly.

The structure of the operating rod portion 32 using connector 34 is not necessary for all operating rod portions 32 extending within each top plate receiving structure 4. That is, this applies not only to two leg units belonging to one group, but also to three or more leg units belonging to one group. One operating rod section 32 extends directly into the top plate receiving structure 4 without using the connector 34 (third rod section), and all remaining operating rod sections 32 may have a structure that uses the connector 34. The operating rod section 32 that extends directly into the top plate receiving structure 4 serves as a reference operating rod section when synchronizing with the other operating rod sections 32. That is, the operation unit 30 is operated in the state of loosening the small screws 34 c and 34 c in all the connectors 34 used, the third rod portion, which extends into the top plate receiving structure 4, is brought into contact with the push valve 16 of the air spring 13. In this state, in the remaining operating rod sections 32, the air spring operating portion 36 formed at the tip end of the second rod portion 33 b can be brought into contact (only in contact and not pushed in) with the push valve 16 of the air spring 13, by adjusting the amounts of insertion and rotation angle of the first rod portion 33 a and the second rod portion 33 b relative to the connector 34. In this state of contact, all the small screws 34 c, 34 c are secured to the connector 34 by screwing into the connector 34, the first rod portion 33 a and the second rod portion 3 b are fixed to the connector 34, the operation unit 30 may be a one-piece assembly structure. Then, when the user operates the operating section 30, in all of the operating rod sections 32 including the third operating section, the operation on the handle portion 31 is not absorbed midway, but transferred to all of the air spring operating portions 36, allowing all of the push valves 16 of the air spring 13 to perform in synchronized operation.

FIGS. 5A-5B illustrate the tilt of the top plate for the tilt-adjustable table shown in FIGS. 1A to 4C. The same symbols are used in FIGS. 5A-5B for elements or parts that are equivalent to the elements or parts shown in FIGS. 1A-1C. In the state shown in FIG. 5A, the length of the support column 5 belonging to the first leg unit group G1 and the length of the support column 5 belonging to the second leg unit group G2 have the same length. In this condition, the top plate 2 is in a horizontal state. Here, the length of the support column 5 belonging to the second leg unit group G2 is maintained, but only the length of the support column 5 belonging to the first leg unit group G1 is changed, the attitude of the top plate 2, as shown in FIG. 5B, is such that the height of the side located on the support column 5 belonging to the first leg unit group G1 is heigh, but the height of the other side located on the support column 5 belonging to the second leg unit group G2 is low. As a result, the top plate 2 is tilted indicated by the tilting direction S. Since the foot body part 7 is fixedly mounted on the support column 5, the top plate 2, when the support column 5 is tilted, the foot body part 7 is also tilted with the support column 5. A foot portion 8 a is attached to the foot body portion 7 so that the height of protrusion in the direction toward the floor surface F (height direction) with respect to the foot body part 7 can be changed by an operation of the foot shaft 9 a. Therefore, even if the foot body portion 7 is tilted with the top plate 2, it is possible to rest the foot portion 8 a, 8 b at the same time on the floor surface F and the load of the table 2 can be transmitted to the floor surface F. Foot portions 8 a, 8 b are connected to foot shafts 9 a, 9 b respectively by ball joints 47 (FIG. 3C), so that the angular deviation caused by the tilt of the top plate 2 is absorbed. The overturning moment generated in the table 1 with the tilt also is encountered against the endurance of foot parts 8 a, 8 b.

FIGS. 6A-6B are perspective views partially representing another embodiment of the table of the present invention. FIG. 6A is a perspective view representing the non-tilted state of one support column of the table and its legs, and FIG. 6B is a perspective view representing the tilted state of the table. In the case that the leg structure of the table la is the leg structure 3 a consisting of four leg units U1 to U4 each disposed correspondingly to the four corners, all of the support columns 5 and the foot sections 6 have the same structure as shown in Figure. The foot structure 3 a of the table la shown in FIGS. 6A-6B has the structure in which the lower end part 5 b of the support column 5 (the lower end part of the connecting cylinder 5 c) is connected to the foot body part 7 of the foot 6 at any angle only around the axis L1 parallel to the tilt axis in the tilt direction T (FIGS. 1A-1C). Therefore, in this embodiment, the top plate 2 can be tilted as shown in FIG. 6B only to the direction shown in S and the opposite direction against it.

FIG. 7A-7B are explanatory views showing the connection structure of a foot section and a support column of the leg structure shown in FIGS. 6A-6B.

FIG. 7A is an explanatory view showing an example of the connection structure of a support column 5 and a foot section 6 of the leg structure 3 a shown in FIGS. 6A-6B.

FIG. 7B is an explanatory view showing another example of the connection structure of a support column 5 and a foot section 6 shown in FIGS. 6A-6B.

In FIG. 7A and FIG. 7B, I is a plan view of a support column 5 and a foot section 6 of leg structure 3 a viewed from above, II is a view showing three washers sandwiched between a support column 5 and a foot section 6 side-by-side, Ill is a side view showing I in partial section, and IV is a view showing the sleeve used for the side of a support column 5, and V is a view showing the attachment bolts and washers used for the connection structure.

Referring to FIGS. 6A-6B and FIGS. 7A-7B, in the leg structure 3 a, an adapter 50 with a block shape is fixedly mounted on the lower end portion 5 b of the support column 5. The adapter 50 is located in a contact state with the side surface 7 a of the foot body portion 7, which faces the inside of the table, in this state the adapter 50 is fixed to the foot body portion 7 by tightening the threaded knob 51 (attachment bolt) in the direction of the axis L. The foot body portion 7 is fixedly mounted with a nut 60 into which the male screw of the knob 51 can screw, a sleeve 61 is mounted in the adapter 50 in alignment with the nut 60 mounted on the foot body portion 7. A lock washer assembly 62 is clamped between the foot body portion 7 and the adapter 50. The washer assembly 62 consists of three washers, that is, ring washers 63, 63 disposed on the side of the foot body portion 7 and on the side of the adapter 50 and a spring washers 64 sandwiched between the ring washers 63, 63. The spring washers 64 are formed in a C-shape and formed by waving in the clamp-in direction. The threaded knob 51 comprises an outer threaded portion 65 and a knob portion 66. In addition, the lower end portion 14 of the outer cylinder 11 of the air spring is applied to the connecting cylinder 5 c. The deformed portion of the connecting cylinder 5 c, which protrudes into the cylinder as the embossing 68, is positioned in a position where the lower end portion 14 of the outer cylinder 11 no longer descends by abutting against the deformed portion. Alternatively, by bringing the front end of the screwed-in set screw 69 into contact with the lower end portion 14 of the outer cylinder 11 on the outside of the connecting cylinder 5 c of the support column 5, the outer cylinder can also hold the outer cylinder 11 in place on the connecting cylinder 5 c.

The male threaded portion 65 of the knob 51 is made to pass through the sleeve 61 and the washer assembly 62, and then the male threaded portion 65 is screwed into the nut 60 in the foot body portion 7, the support column 5 being attached to the foot body portion 7. The male threaded portion 65 screwed into the nut 60 is able to extend into the foot body 7. The screw can be loosed by manipulating the knob 51, and the connection between the foot body portion 7 and the adapter 50 is made free. When tightened with knob 51, the spring washer 64 elasticity prevents the screw from loosening. Washer 67 is also inserted between the key portion 66 of knob 51 and adapter 50, this structure ensures that the threads of knob 51 with threads are securely tightened. The relative mounting angle of the adapter 50 against the foot body portion 7 can be changed depending on the tilt of the top plate 2. When the mounting angle is determined, the knob 51 is screwed in by operation, and the tilt angle of the support column 5 can be fixed and maintained as shown in FIG. 6B. The attitude of the foot body part 7 does not change relative to the ground F even if the tilt angle of the top plate 2 changes, so that all the foot portions 8 set on the foot body part 7 are in the state of correctly facing the ground F. The male threaded portion 65 of the knob 51 may penetrate the foot body portion 7, another nut can be tightened and fixed to the end of the protruding male threaded portion 65, with this threading structure, the support column 5 being securely fixed to the foot body portion 7.

The connection structure of the support column 5 and foot section 6 shown in FIG. 7B is a connection structure, in which the knob 51 with male threaded portion is directly threaded on the connecting cylinder 5 c of the support column 5, thereby the support column 5 is connected with the foot body portion 7. In other words, the foot body portion 7 is provided in the fixed manner with a nut 70, and a sleeve 71 is mounted in the lower part of the connecting cylinder 5 c in a penetrating state. A washer assembly 72 is provided between the nut 70 and the lower part of the connecting cylinder 5 c for preventing slack. The washer set 72 is three sets of washers such as with washer assembly 62 shown in FIG. 7A, and consists of the ring washers 73, 73 and their C-shaped spring washers 74 sandwiched between them. The knob 51 with screw as attachment bolt has the same structure as knob 51 with screw shown in FIG. 7A, but symbolized by male threaded portion 75 and knob portion 76. In addition, washers 77 same as washer 67 are intervened between the knob portion 76 of knob 51 with thread and the support column 5.

The externally threaded portion 65 of the knob 51 passes through the sleeve 71 and washer assembly 72 provided in a penetrating state in the connecting cylinder 5 c, and the externally threaded portion 65 is screwed into the nut 70 secured to the foot body portion 7, then the support column 5 is secured to the foot body portion 7. The externally threaded portion 65 screws into the nut 60 and can extend into the foot body portion 7. The connection of the foot body portion 7 and the adapter 50 is made free by loosening the screw by operating the knob 51. When tightening with the knob 51, the spring washer 72 prevents loosening of the screw. A washer 77 is also clamped between the knob portion 76 of the knob 51 and the support column 5 to ensure that the threaded knob 51 with threads is screwed. The mounting angle of the support column 5 relative to the foot body portion 7 can be changed according to the inclination of the top plate 2 in the same manner as in the case of the connection structure shown in FIG. 7A, so that the description again is omitted. Also, the embossing 78 and fixing screw 79 formed on the connecting cylinder 5 c to fix the outer cylinder 11 of the air spring are the same as those about the embossing 68 and fixing screw 69 in FIG. 7A, so they are omitted.

FIGS. 8A-*B are views showing a further embodiment of the table of the present invention. FIG. 8A is a perspective view showing the whole of the further embodiment of the table according to the present invention, and FIG. 8B is a perspective view showing a part of the embodiment in an enlarged manner. In the table 1 b shown in FIGS. 8A-8B, the foot section 6 provided in the support column 5 belonging to the first leg unit group G1 and the foot section 6 provided in the support column 5 belonging to the second leg unit group G2 (adjacent to the foot section 6 belonging to the first leg unit group G1) are connected by the connecting member 55. In this example the connecting member 55 includes an elongated plate member 56 which is formed at both ends with long holes 57,57 extending in the long axis direction. The elongated plate member 56 is connected by butterfly bolts 58, 58 through the long holes 57, 57 into the foot body portions 7,7 of the foot sections 6, 6. In the state where the butterfly bolt 58,58 are loosened, the connecting member 55 can absorb, within the range allowed by the long holes 57, 57, the variation in the spacing or rotation of the two foot sections 6, 6 approaching and separating from each other according to the inclination of the top plate 2. The first operation unit 301 and the second operating unit 302, the foot portions 8 a, 8 b are the same as those shown in FIGS. 1A-1C.

When the tilt angle of the top plate 2 is determined, by screwing the butterfly bolt 58, 58 through the long hole 57, 57 into the foot body portion 7, 7 of the two leg unit groups G1, G2 in the state of the elongated plate member 56 being clamped against the foot body portion 7, 7, the foot sections 6, 6 are connected by the connecting member 56. In this connected state, the connecting member 55 also suppresses the displacement of the foot section 6, 6 from shifting or twisting laterally with each other, so the rigidity of the leg structure 3 b can be improved and contributes to stability. The elongated plate member 56 is shown as one member, but the elongated plate member 56 can also be formed as a connecting part consisting of two parts bolted to two foot sections 6, 6 respectively and overlapping each other with long holes.

In each of the above embodiments, both the first leg unit group G1 and the second leg unit group G2 include two support columns 5,5, but each group can simply include more than one support column 5. However, one of the groups preferably includes two support columns. Also, in the case of a large table, etc., either one or two support columns or even three support columns can be included depending on the size and shape of the top plate 2. FIG. 9 is a perspective view showing a further embodiment of the table according to the present invention. In FIG. 9, the same elements and parts as those shown in FIG. 2 are used with the same symbols as those used in FIG. 2. FIG. 9 is a perspective view of the table 1 c shown in representing the table from the back side. The first leg unit group G1 includes three leg units U1, U2 and U5 arranged in a row along the one side edge “a”, the second leg unit group G2 includes three leg units U3, U4 and U6 arranged in a row along the other side edge “a”. The leg unit U5 (U6) is located in the middle position between the leg units U1, U2 (leg units U3, U4). The operation units 301, 302 have, in order to operate the corresponding the leg units U5, U6, the second rod portions 33 c, 33 c branching vertically in the direction of the center of the table 1 c from the central portions of the first rod portions 33 a and 33 a of the rod sections 33, 33 and extending toward the interior of the top plate receiving structures 4, 4 of the leg units U5, U6. Each second rod portion 33 c includes a lever pivot portion 35 and an air spring operating portion 36 identical to the other second rod portion 33 b (also with reference to FIGS. 4A-4C). Operating the operation unit 301, the leg units U1, U2, U5 belonging to the first leg unit group G1 operate simultaneously (each support column 5 changes its length), and by operating the operation unit 302, the leg units U3, U4, U6 belonging to the second leg unit group G2 operate simultaneously (each support column 5 changes its length). This embodiment is particularly preferred in the case of a large table with a long lateral length or a large load loaded on the table.

As explained above, the operation unit 30 is provided with a structure such as a lever structure having a tip end portion 36 moved up and down by the lever action with the lever pivot portion 35 located in the middle position, the tip end portion 36 operating to push down the push valve 16. In addition, as another structure of the operating unit 30, the operating tip end portion with a tapered surface is operated so that the tip end portion moves forward and backward, that is, in and out of the inner part of the top plate receiving structure. In this case, the push valve 16 is operated by the wedge action of the tapered surface of the operating tip end portion.

FIG. 10 is a perspective view showing a further embodiment of the table according to the present invention. The table 1 d shown in FIG. 10 is provided, for example, with four support columns 5 in a manner corresponding to the four corners of the top plate 2, positioned to match each vertex of the rectangle, and two sets of first operation units and second operation units are provided. That is, the first leg unit group G1(i) and the second leg unit group G2(i) as one group of the leg unit groups are arranged along the long side edges “a”, “a” of the top plate 2, as in the case of the first leg unit group G1 and the second leg unit group G2 in the embodiment shown in FIG. 2. From the same four leg units U1 to U4, another group of the leg unit groups is defined which includes the first leg unit group G1(ii) and the second leg unit group G2(ii) arranged along the short side edges “b”, “b” of the top plate 2. The four leg units U1 to U4 are shown as examples occupying positions consistent with the four respective vertices of the rectangle, but the top plate 2 can be a parallelogram. Even though configured in a position consistent with those four respective vertices, the tilt directions, although not at orthogonal angles to each other, will give the same effect.

With respect to the operation units, one set of the first operation unit 301(i) and the second operation unit 302(i), like the first operation unit and second operation unit 301, 302 in the embodiment shown in FIG. 2, are arranged along the long side edges “a”, “a”, but the first operation unit 301(ii) and the second operation unit 302(ii) of another set of the operation units are arranged along the short side edges “b”, “b” of the top plate 2. The structure of the first operation unit 301(ii) and the second operation unit 302(ii) of the other set of the operation units is the same structure of the first operation unit 302(i) and the second operation unit 302(i) of the one set of the operation units, except that the lengths of the units are different, so the description is again omitted. By operating another set of first operation unit 301(ii) and second operation unit 302(ii), the top plate 2 can be tilted in the tilt direction S(ii) orthogonal to the tilt direction S(i) while operating the one set of the first operation section 301(i) and the second operation section 302(i). Regarding the top plate receiving structure 4 a used in this embodiment, it will be described later with reference to FIG. 11.

FIG. 11 is a perspective view of the operating unit and the top plate receiving structure in the embodiment shown in FIG. 10. In the top plate receiving structure 4 a shown in FIG. 11, there are longitudinal long holes 25,25 in the side wall portions 22,22 on both sides of the pinch angle. A second rod portion 33 b of the first operating unit 301(i) of the one set of the units and a second rod portion 33 b of the second operating unit 302(ii) of the other set of units pass through the long holes 25, 25 and into the central concave portion 21 of the top plate receiving structure 4 a. The lower edge portions of the long hole 25,25 are lever pivot portions 35,35. When operating the first operating unit 301(i) of the one set of the units and second operating unit 302(ii) of the other set of the units, the second rod portions 33 b, 33 b operate by the lever action of the lever pivot portions 35,35 to cause the air spring operating portions 36,36 formed on the tip end portions of the second rod portions 33 b, 33 b to act in the up and down direction. The air spring operating portions 36,36 overlap up and down each other on the push valve 16 in the concave portion 21.

When only the first operation unit 301(i) is operated, the air spring operating portion 36 formed at the tip end of the second rod portion 33 b of the first operation unit 301(i) directly pushes the push valve 16 in, causing the air spring to act. When the second operation unit 302(ii) is operated, the air spring operating portion 36 formed at the tip end of the second rod portion 33 b of the second operating unit 302(ii) pushes the air spring operating portion 36 of the first operating unit 301(i), thereby the air spring operating portion 36 of this first operating unit 301(i) presses the push valve 16, causing the air spring to act. Regarding the other components of the top plate receiving structure 4 a, since the structure is the same as that of the top plate supporting structure 4 shown in FIGS. 4A-4C, the same symbols are used and the description is omitted.

FIGS. 12A-12D are explanatory views showing the rotational configuration of the foot section of the leg unit of the table according to the present invention. Since the support column 5 of the structure has a circular cross section, the support column 5 is mounted on the foot body portion 7 of the foot section 6. However, it is easy to change the angle around the axis of the support column 5 for mounting. The direction in which the foot body portion 7 of the foot section 6 extends is changeable, corresponding to the combination of the set to be operated of the first leg unit and the second leg unit and the tilt direction of the top plate 2, by adopting, for example, a structure in which protrusions and concave parts embedded with the protrusion are formed in 90 degrees around the axis of the support column 5, or the bottom of support column 5 is fixed with screws at each 90 degrees. Taking FIG. 12A as the basic shape, assuming that one set of the first leg unit group and the second leg unit group is arranged the long side edge “a” of the top plate 2, the inclination (downward) direction S of the top plate 2 produced by the operation is from the position of the foot portions 8 a, 8 b toward the lower side of the figure surface.

FIG. 12B shows the state in which the foot body portion 7 is rotated 180 degrees from the configuration of FIG. 12A. The first support column group and the second support column group being operated are unchanged from the basic shape, but the top plate 2 is tilted in the opposite direction, and the tilting (downward) direction S is toward the direction of the face side of the figure. FIG. 12C shows the state in which the foot body portion 7 is rotated 90 degrees clockwise from the configuration shown in FIG. 12A. The tilt (downward) direction S in this state is in the direction toward the left side of the figure face based on the position of the foot portions 8 a, 8 b. The set of the first leg unit and the second leg unit to be operated is different from the set in the case of the basic form (another set along the short side edges “b”,“b”). FIG. 12D shows the state in which the foot body portion 7 is rotated clockwise starting from the configuration of FIG. 12A, indicating a rotation of 270 degrees. The tilt (downward) direction S in this state is the direction toward the right side of the figure based on the position of the foot portions 8 a, 8 b. The set of the first leg unit and the second leg unit is same as that of FIG. 12C (the other set along the short side edges “b”, “b”), but tilted in the opposite direction of operation. In any case, the foot body portion 7 is within the projection of the top plate 2 toward the ground F, and does not protrude beyond the projection of the top plate 2, it does not interfere with operators moving around.

FIGS. 13A-13B are schematic diagrams showing the embodiment of the table according to the present invention, applied to a table with laterally long shape, and when looking from a foot body portion toward the top plate. Table le shown in FIG. 13A is, for example, a table of a top plate 2 that is laterally very long (long side edges “a”, “a” is sufficiently longer than short side edges “b”, “b”). Since the leg structure 3 including the support column and foot section is the same as the structure shown in FIGS. 3A-3C and FIGS. 12A-12D, a detailed description is omitted here. Table 1 e has so long lateral length that one person cannot operate two operating sections 30, 30 arranged along the short side edges “b”, “b” at the same time. However, two people can share and operate these operating sections 30, 30 and change the length of the support columns of the first leg unit group G1 and the second leg unit group G2 along the short side edges “b”, “b”. The height of the top plate 2 is adjusted in the case where the lengths of the changed support columns of the two leg unit groups G1, G2 are the same, in case differently adjusted, the height is changed and tilted in the tilt direction (lateral) S. The operation units 30,30 may be arranged along the long side edges “a”,“a” as shown in the table 1 f in FIG. 13B. In the table 1 f, except for the configuration of the operation unit 30,30 and the leg units G1, G2, the same symbols are given to the same structure as in the table 1 e so that the description again is omitted. In the case of the table 1 f, it is possible for one person to operate two operation units 30,30, with the tilt direction S being longitudinal.

FIGS. 14A-14B are schematic diagrams showing other embodiments of the table according to the present invention. The table 1 g shown in FIG. 14A has a top plate 2 b in the shape of a circular. As the leg structure, the first and second leg unit groups and the leg units, the same structure or unit can be used as that used for the leg structure 3, the first and second leg unit groups G1,G2 and leg units U1 to U4 as shown in FIGS. 1A-1C and so forth. The shape of the top plate 2 b may be an L-shaped top plate, as shown in the table 1 h in FIG. 14B. In this case, the first and second leg unit groups G1 and G2 of the leg structure can be arranged so as to cross an L-shape diagonally. The lengths of the first and second leg unit groups G1 and G2 along the table surface (length of the operation section 30) are of different lengths, but the leg units U1 to U4 can be of the same structure. Not only to the L-shaped table, the same leg structure can be used for half-circle tables, quarter-circle tables, even for fan-shaped tables.

Above, for the tiltable table of the present invention, several examples are listed for illustration, but various variations are optional. For example, the seating body 8 c of the foot portion 8 may be a caster in order to be able to move on the floor surface F, or a caster with a rotation stop locking function. The top plate, although illustrated as a flat plate, can take various forms depending on the application. For example, the present table can be applied to an arbitrary lifting platform such as a bed or sofa where the top plate is a supporting base for a cushion or a pad.

In addition, the table according to the present invention is applicable to tables in general, such as a stove, a steering rack, a line stand, store stand, display table, study table, etc., which has a horizontal or nearly horizontal surface for placing items thereon and for operator's working while standing or sitting nearby, and has a function necessary for the up and down movement of the top plate.

DESCRIPTION OF THE SYMBOLS

-   1, 1 a, 1 b, 1 c, 1 d, 1 e, 1 f, 1 g, h table -   2, 2 a, 2 b top plate -   3, 3 a, 3 b leg unit structure -   4, 4 a top plate receiving structure -   5 support column 5 a upper end portion 5 b lower end portion -   6 foot section -   7 foot body portion -   7 a side -   8(8 a, 8 b)8 c seating body -   9 leg shaft 9 a long leg shaft 9 b short leg shaft -   10, 10 a foot connector -   11 inner cylinder -   12 outer cylinder -   13 air spring -   14 lower end section of outer cylinder 11 -   15 upper end section of inner cylinder 12 -   16 push valve -   17, 17 a locking structure -   21 central recess -   22 side wall section -   23 bottom wall section (bottom) -   24 fastener(fixing member) -   25 long hole -   26 flange part -   30(30 a,30 b) operation unit -   31 handle portion -   301, 301(i), 301(i) first operation unit -   302, 302(i), 302(i) second operation unit -   32 operating rod section -   33 operating rod section -   33 a first rod portion -   33 b second rod portion -   34 connector -   34 a, 34 a hole -   34 b, 34 b screw hole -   35 lever pivot portion -   36 air spring operating portion -   40 screw shaft -   41, 42 nut -   43, 44 washer -   45 screw shaft -   46 screw hole -   47 ball joints -   50 adaptor -   51 knob -   56 elongated plate member -   57 long hole -   58 butterfly bolt -   60, 70 nut -   61, 71 sleeve -   62, 72 group of washers -   63, 73 circular washer(washer) -   64, 74 spring washer -   65, 75 external thread part -   66 key portion -   67, 77 washer -   68, 78 embossing -   69, 79 fixed screws -   68 long axis -   76 knob portion -   S, S(i), S(ii) tilt direction T optimum tilt direction -   F floor -   L horizontal centerline -   L1 axis -   G1, G1(i), G1(ii) first leg unit group -   G2, G2(i), G2(ii) second leg unit group -   6G1 first foot section group -   6G2 second foot section group -   U1, U2, U3, U4, U5, U6 leg unit -   P1 first support column configuration plane -   P2 second support column configuration plan 

1. A table provided with a top plate, a plurality of leg units and a plurality of operation units, said each leg unit has a support column and a foot section, said support column has upper and lower ends, the length of the direction connecting the upper and lower ends being changeable, and the upper end being connected to the top plate, and said foot section is connected to said lower end of said support column and is adapted for seating on the floor, said lengths of said support columns of said plurality of leg units are changeable by operating one or more said operation units, wherein said each leg unit belongs to either a first leg unit group which includes one or more leg units and arranged on one side of the top plate or a second leg unit group which includes one or more leg unit and arranged on the other side of the top plate, said each operation unit comprises a first operating section for changing the lengths of the support columns of the leg units belonging to the first leg unit group, and a second operating section for changing the lengths of the support columns of the leg units belonging to the second leg unit group, the second operating section being operable independently of the first operating section.
 2. A lifting table according to claim 1, in each of said leg units, said foot section comprises a foot body portion which is mounted on said support column and extends in a direction between said one side of the top plate and the other side, and plurality of foot portions which are spaced in the direction of their extension and are adapted for seating on the floor.
 3. A lifting table according to claim 2, the foot body portion of said leg unit is fixedly mounted on said support column, the foot portions are mounted on said foot body portion in a manner that the length of each foot portion protruding relative to the foot body portion in the direction to the floor can be changed, said protruding lengths of said foot portions relative to the foot body portion can be changed corresponding to the tilt angle of the top plate.
 4. A lifting table according to claim 2, the foot body portion of said leg unit is mounted on said lower end of the said support column in a manner that the mounting angle can be changed, the mounting angle of the foot body portion relative to said support column can be changed corresponding to the tilt angle of the top plate.
 5. A lifting table according to claim 1, both the first and second leg unit groups have more than two leg units, the support columns of the leg units belonging to the first leg unit group are in a common first support column configuration plane, the support columns of the leg units belonging to the second leg unit group are in a common second support column placement plane, said first configuration surface and second configuration surface are parallel to each other.
 6. A lifting table according to claim 1, said foot portions mounted on the support columns of the leg unit belonging to the first leg unit group and said foot portions mounted on the support columns of the leg unit belonging to the second leg unit group are connected by the connecting member so that the relative position changes of the both said foot portions resulting from the inclination of said top plate can be absorbed.
 7. A listing table according to claim 1, said leg units includes four leg units, each arranged at point corresponding to the four vertices of the parallelogram, said one side and said other side of the top plate are the two opposite sets of sides of said parallelogram, with respect to each of the two sets of sides of the top plate, said foot units are defined as belonging to either a first leg unit group or a second leg unit group, and two operating sections are defined as belonging to either a first operating section or a second operating section.
 8. A lifting table according to claim 7, said each leg unit includes a top plate support structure that is mounted on the top plate and the upper end of the support column, for connecting the upper end of the strut to the top plate, in each of said leg units, one of the operating sections belonging to said first operating section and one of the operating sections belonging to second operating section extends into said top plate support structure, and the length of the support column can be changed by operating either of said two operating sections.
 9. A lifting table according to claim 1, the foot sections are rotatably mounted on said support columns according to the selected tilt direction so that the direction in which said foot body portion extends follows said tilt direction.
 10. A lifting table according to claim 1, the height of the top plate can be changed by changing the support column lengths of the leg units belonging to the first and second leg unit groups to the same length. 